Multiple utility grinder



May 10, 1955 J. J. MILLER MULTIPLE UTILITY GRINDER 3 Sheets-Sheet 1Filed April 17, 1953 May 10, 1955 J. J. MILLER 2,707,855

MULTIPLE UTILITY GRINDER Filed April l'7, 1953 5 Sheets-Sheet 2 -BYMWJ."J. MILLER MULTIPLE UTILITY GRINDER May 10, 1955 Filed April 17, 195:5

3 SheetsSheet 3 United States Patent MULTIPLE GRINDER Joseph J. Miller,San Francisco, Calif.

Application April 17, 1953, Serial No. 349,530

1'0'Claims. (Cl. 51-166) scommon .operatingmeans for all .of thegrinding-wheels with control meansoperative to applypower only :to thegrindingtwheel disposed ,at the; grinding station, wvhile all ,ofrtheother grinding :wheels remain inactive.

It is still further proposed to provide an individual ,guard for eachg-grinding wheel, each ,guard having ,a discharge conduit :for flying;particles of dust =adaptednto :line up .with: ,a :common discharge ,when,the guard 1 is disposed .aLthe grinding station.

Another .object ;of the present inventionis to provide for avariable,speedtransmission between a .motorandthe ,gr'inding wheels.tocornpensatefor loss of surface speed due :to the .wearing ,down of rthe; grinding wheels.

A still further object of the invention is to provide for .a mountingmeansfor'the turret -,on one ,sideof a supporting pedestal whichmay bereadilyduplicated ontheother ,side of the pedestal for doubling thecapacity sof "the machine.

,Andfinally it is proposed to provideza. machine :of the .characterdescribed that is relativelysimple .in construc- -tion, .easy .to.adjust and operate, economic :in operation, .andinwhich-all thepartstand particularly the wheelatthe operating station are readilyaccessible,-resulting insaving inztirne-and labor.

I ,Furtherobjects .and advantages ofmy vinventionpW-ill appear as thespecification progresses, ,and the :new and useful features of myMultipleUtility Grinder will .be .fully defined in the-rclaims attached.hereto.

The preferred form of my invention .is illustrated .in

the-accompanyingdrawings, forming-part of this-tapplica' i .tion, ;inwhich:

Figure lgshows-taniend viewof my Multiple Grinder; Figure 2, a sideviewof-the same, with ,parts :shown in section;

:Figure 3, an enlarged detail section taken along wline .3-.3 of Figure2;and

Figure.4, a section taken along line 4-4 ,of.-Figure ,3. While [I haveshown only the preferred form'ofe'the invention, it 'shouldbe understodthat'various changesor modifications maybe madewithin the scope of .theiclaims attached hereto without departing from the SPilitgOf theinvention.

:Referring to the drawings in detail, my Multiple Grinder comprises. inits principal .features :a pedestal .-1

terminating, at its upper end, in a transverse housing ;-2,.a a;

horizontal shaft 3-revo1vable in thehousingand having a large ,gearwheel .4. fixed to theouterend.thereof acaln ,SfiXCdIO the ,outer ,end.of .the-housinganearthe-gear wheeh a drum or turret.;6 revolvable .or:tur-nablesonthe housing and .provided with anannular.seriesofstuhsshafts 252';

7 having grinding wheels 8 secured thereon outside the tdrum, a-roller,-9 on;eachzstub .shaft cooperating with the cam in establishingdriving relation between the gear Wheel, and the stubshaft disposed atthe grindingstation, .a 11110101 11 vertically adjustable in thepedestal and .a driving-connection including abelt 12between-the motor,and the main shaft 3 designed to change the speed ratio in response tovertical adjustments of-the motor.

-'=1"he;pedesta1 1 may be of anysuitableform.and height andis hollow toaccommodate various drive elements :therein. The-housing 2 liestransversely over the: pedestal tandhas reduced cylindrical extensions13 projecting .in opposite directions, which makes it possible .tosupport two complete turret arrangements thereon. Only one (has beenshown asbeing suflicient to-explain the,present invention.

The shaft 3 is revolvable in the housing in bearings 14 sandhas'the gearwheel 4secured upon the outer endthereof, the gear wheel beingin theform of a *disc having .an linwardly'off-set section to bring the gear.teeth ,in conveniently .close relation to the cam 5.

"The latter has-a generally'circular cam face of slightly longerdiameter thanthatofthegear'wheel :and is fixed upon the end of thehousing extension.13, :as at 15. At ltherqperating or grinding station,which is .locatedatthe horizontal central plane :of the turret, thesurface of the .camtiscut.back, ..and,at this location the cam ,has,asfitting lfipsecured "thereto :Which provides ,a short .cam face v17see Figure A.) concentric with, .but drawn to a slightly smallerdiameterthanthe main cam surface, with suitable ggraded approachesJSmergingjntothe main camface.

=The fittingrldalso carries an outercam .19 spacedfrorn :the cam 17andconcentric therewith-so .asto form a track 520 withthesamethe outer:cam'merging into the inner iacerof thedrumo through approaches 21gradedtorun I parallelto the .approaches 18.

The drum 6 is revolvable on the extension 13 of the :housing 2, througha bearing v22, and comprises a hub 23, zanend -member,24 and acylindrical wall 25 extending over thecam .5 and the gear wheel 4 andbeyond .the :same andbeing made --of an inner diameter in excess oftherouter diameter of the cam, so as' tovform a track26 therewith.

.Fhe drum has .the annular series of stub shafts -7 mountedtherein, withthe rollers9 on theshafts arranged ttO ridein-the track 26 andthe track20 communicating therewith. The-shafts are secured to the inner face ofthe drum by means of drag links 27 pivoted, at one end, as. at 2.7,intsmall brackets 28 projecting inwardly from the drum :inevenly spacedrelation and terminating, at their free ends,.in sleeves 29 extendingtransverselyof the drum-andhav-ingthe-stub shafts 7 revolvably mountedtherein, through bearings 30.

.The free endsof thegstub shafts 7 and the sleeves .29 extendlthrough anend plate 31 secured uponthe free end .ofthe-drum:and.are guided inslots 32, whichare made arcuate on the radii of the pivots 27 to allowof swinging movement of the drag links in the manner necessary for.t-he.operationiof the machine.

It-will be'noted that, when the -drum'is revolved or turned, it dragsthe stub shafts 7 along with it, .through ,the

. drag-.linksll and that the swinging movement :of ;the

,dragilinks is controlled by the rollers 9 ridingin the:tracks 26gand,20,.respectively. As long as the rollers aredisposedinthe tracks26, Which extends over the major portion of the cam 5, the shafts areheld relatively close to the Wall of the drum. When the rollers enterthe track 20, they -,are crowded inwardly, that is, toward the center of,the drum, .and move the shafts correspondingly, as shown in Figure 4.

The-stuhshafts .carry pinions 33 arranged in opposing relation,touthegear wheel and, as long as the -rollers .9 ride in the main track26, the pinions are held out of engagement with the gear wheel, but whenthe rollers 9 pass through the short track 20, carried by the cam 5 atthe grinding station, the pinions are made to enter into engagement withthe gear wheel, attaining a position of full engagement at the centralhorizontal plane of the drum, as shown in Figure 4.

Each stub shaft 7 is automatically locked in central position at thegrinding station by means of a springpressed plunger 34 cooperating witha pin 35 projecting from the end wall 24 of the drum opposite eachshaft, the plunger having a head 36 with a central recess fitting thepin and a slanting approach 37 to the recess, whereby on a turningmovement of the cylinder, the plunger is first pushed back by the pinbearing on the slanting approach and then snaps into place over the pinfor locking the same in central position.

The engagement may be released manually by means of the handle 38pivoted to the housing 2, as at 39 (see Figure 2) which operates theplunger through a link 40 for retracting the plunger.

The main shaft 3 carrying the gear wheel 4 is driven by the motor 11through a chain drive comprising a chain 41, a sprocket 42 on the mainshaft 3 and a sprocket 43 on an intermediate shaft 44 mountedtransversely in the pedestal, and through a V-belt drive including apulley 45 on the shaft 44, a pulley 46 on the motor shaft and a V-belttrained over the two pulleys.

Since a grinding wheel works most satisfactorily at a given surfacespeed, and since the surface speed naturally decreases as the diameterof the wheel decreases, due to wear, it is desirable to provide a simplemeans for varying the R. P. M. speed to compensate for a decrease insurface. This I accomplish by making the pulley 46 of the Vari-Speedtype, well-known in the market, which is built on the principle ofmaking one of the flanges of the V-pulley movable with respect to theother and of using spring pressure for urging the movable flange towardthe fixed flange. Thus the active diameter of the pulley is determinedby the belt pressure operating against spring pressure.

In the present structure, the variable pulley 46 is mounted on the motorshaft, and the motor is mounted in a cage 47 slidable in the pedestaland suspended from a screw 48 operable to raise and lower the cage whenrotated by means of a bevel gear drive 49 and a handle 50.

In the position shown in Figure 2, the motor is set relatively low,causing the /-belt to engage in the bottom of the pulley groove anddriving the gear wheel 4 and the grinding wheel at the grinding stationat relatively low speed, which would give the proper surface speed for anew grinding wheel.

If it becomes desirable to increase the speed ratio, the operator merelyraises the motor by operation of the handle 50. This causes the belt toclimb out of the bottom of the groove in the pulley 46, due to thespring action, and to use a larger diameter of the pulley for insuring ahigher speed ratio. Thus, by gradually raising the motor, the operatoris able to compensate for the gradual wear on the grinding wheel and tomaintain a uniform surface speed.

Each of the grinding wheels is provided with its own guard 51, theguards being mounted upon the outer ends of the sleeves 29 and movingwith the grinding wheels to the grinding station.

Each guard is cylindrical in form to surround its grinding wheel inslightly spaced relation thereto, and has an opening, as at 52, to giveaccess to the wheel at the grinding station where a suitable tool orwork rest is provided, as at 53.

Each guard is also provided with a discharge conduit 54 for dustparticles, leading eenterwise to a collecting chamber 55 from which itis exhausted through a port 56 connecting with a hose 57.

The operation of my multiple utility grinder should be readilyunderstood from the foregoing description.

Upon selecting the grinding wheel he intends to use, the operator turnsthe drum to bring the desired wheel opposite the grinding station.During this operation the rollers 9 ride in the tracks 26 and 20,respectively, holding all the pinions 33 except one out of engagementwith the gear wheel 4, while one of them passes through the grindingstation and passes through a position of engagement and out again.

The operator holds the handle 38 to prevent locking at the grindingstation until the selected grinding Wheel reaches the station, when hereleases the handle to automatically lock the wheel in central position.

The operator may then inspect the condition of the selected gear wheeland adjust the motor by operation of the handle 50 to insure the propersurface speed.

Next, he will press one of the buttons 58 to start the motor, anddriving power will be transmitted from the motor through the V-beltdrive 12., the sprocket drive 41, the shaft 3 and the gear wheel 4 tothe one grinding wheel disposed at the grinding station, while all theother grinding wheels remain inactive, due to their relative positionswith regard to the cam 5.

I claim:

1. In a multiple grinder, a main shaft rotatable on a horizontal axisand having a gear wheel mounted thereon, a fixed member having aco-axial annular cam adjacent the rim of the gear wheel, a drum turnableon the axis of rotation and having an inner annular cam facing the firstcam to form a track therewith, a plurality of drag links pivoted to theinner wall of the drum and having stub shafts revolvable in the freeends therof, rollers on the stub shafts extending into the track, andpinions on the stub shafts facing the gear Wheel, the track beingpositioned with respect to the gear wheel for normally spacing thepinions therefrom, and the fixed cam having means for urging any one ofthe pinions into meshing engagement with the gear wheel when the saidpinion passes a designated station due to the turning movement of thedrum.

2. In a multiple grinder, a main shaft rotatable on a horizontal axisand having a gear wheel mounted thereon, a fixed member having aco-axial annular cam adjacent the rim of the gear wheel, a drum turnableon the axis of rotation and having an inner annular earn facing thefirst cam to form a track therewith, a plurality of drag links pivotedto the inner wall of the drum and having stub shafts revolvable in thefree ends thereof, rollers on the stub shafts extending into the track,and pinions on the stub shafts facing the gear wheel, the track beingpositioned with respect to the gear wheel for normally spacing thepinions therefrom, and the fixed cam having means for urging any one ofthe pinions into meshing engagement with the gear wheel when the saidpinion passes a designated station due to a turning movement of thedrum, and the drum having means for automatically locking the same whenthe said pinion has reached a position of full engagement with the gearwheel.

3. In a multiple utility grinder, a shaft rotatable on a horizontal axisand having a gear wheel mounted thereon, a drum turnable on the axis ofrotation to encircle the gear wheel, a plurality of stub shafts carriedby the drum outside the gear wheel so as to be movable with the drum andwith respect thereto, the stub shafts having pinions facing the gearwheel, and cam means operable on the stub shafts for normally keepingthe pinions out of engagement with the gear wheel, the cam meansincluding means for urging any one of the pinions into engagement withthe gear wheel when the stub shaft carrying the pinion passes adesignated station due to the turning movement of the drum.

4. In a multiple utility grinder, a shaft rotatable on a horizontal axisand having a gear wheel mounted thereon, a drum turnable on the axis ofrotation to encircle the gear wheel, a plurality of stub shafts carriedby the drum outside the gear wheel so as to be movable with the drum andwith respect thereto, the stub shafts having pinions facing the gearwheel, and cam means operable on the stub shafts for normally keepingthe pinions out of engagement with the gear wheel, the cam meansincluding means for urging any one of the pinions into engagement withthe gear wheel when the stub shaft carrying the pinion passes through adesignated station due to the turning movement of the drum, and the drumhaving means cooperating therewith for locking the same when the pinionhas reached a position of full engagement with the gear wheel.

5. In a multiple grinder, a drum mounted for turning movement on ahorizontal axis, a gear wheel revolvable Within the drum, a drag linkpivoted to the inner face of the drum and having a shaft revolvable inthe free end thereof, a pinion on said shaft opposite the gear wheel,and a cam mounted within the drum and active on the shaft for normallyholding the pinion out of engagement with the gear wheel.

6. In a multiple grinder, a drum mounted for turning movement on ahorizontal axis, a gear wheel revolvable within the drum, a drag linkpivoted to the inner face of the drum and having a shaft revolvable inthe free end thereof, a pinion on said shaft opposite the gear wheel,and a cam mounted within the drum and active on the shaft for normallyholding the pinion out of engagement with the gear wheel, the cam havingmeans for urging the pinion into engagement with the gear wheel when theshaft passes through a designated station on a turning movement of thedrum.

7. In a machine of the character described, a cam having a majorcylindrical portion drawn to the same diameter and a minor cylindricalportion of less diameter, with graded approaches betwen the twoportions, the minor portion having a concentric cam face opposing thesame to form a track therewith, with similarly graded approaches leadingto the latter cam face, and a member turnable on the cam having meansfor dragging a roller over the cam and through the track, the rollerhaving a shaft revolvable therein with a pinion on the shaft, and a gearwheel revolvable concentric with the cam and in the plane of the pinion,with the pinion clearing the gear wheel while the roller passes over themajor portion of the cam and engaging therewith when the roller passesthrough the track.

8. In a multiple grinder, a member turnable about a central axis, anannular series of shafts revolvable in said member and having grindingwheels thereon, a rotary gear wheel mounted inside the series of shafts,

Cir

pinions on the shafts in coplanar relation with the gear wheel andnormally spaced therefrom, and means responsive to a turning movement ofthe said member for meshing any one of the pinions with the gear wheelas the said pinion passes through a designated station, the latter meanscomprising a fixed cam mounted adjacent the gear wheel and rollers onthe shafts riding on the cam, and the cam having a major sectiondimensioned to space the pinions with respect to the gear wheel and aminor track section crowding a roller passing therethrough inwardly toforce its companion pinion into engagement with the gear wheel.

9. In a multiple grinder, a drum mounted for turning movement on ahorizontal axis, a gear wheel revolvable within the drum and having acontinuous set of gear teeth thereon, an annular series of spacedpinions carried by the drum coplanar with the gear wheel and normallydisconnected therefrom, and means for establishing continuous drivinggear connection between any one of the pinions and the gear wheel whensaid pinion passes through a designated station on a turning movement ofthe drum.

10. In a multiple grinder, a drum mounted for turning movement on ahorizontal axis, a gear wheel revolvable within the drum and having acontinuous set of gear teeth thereon, an annular series of spacedpinions carried by the drum coplanar with the gear wheel and normallydisconnected therefrom and means for establishing continuous drivinggear connection between any one of the pinions and the gear wheel whensaid pinion passes through a designated station on a turning movement ofthe drum, the pinions having grinding wheels mounted co-axiallytherewith.

References Cited in the file of this patent UNITED STATES PATENTS1,011,461 Manning et a1. Dec. 12, 1911 1,162,233 Goddu Nov. 30, 19151,628,939 Wells May 17, 1927 1,949,975 Reeves Mar. 6, 1934 1,990,684Wright Feb. 12, 1935 2,003,495 Ritz June 4, 1935 2,092,469 Oslund Sept.7, 1937 2,437,850 Dennis Mar. 16, 1948 FOREIGN PATENTS 468,726 FranceJuly 13, 1914

